Origin - from the fountain pen collector community.

You go to a yardsale which has just opened and expect they might have a whole load of nice pens, pen parts, etc., and then you ask the folks there whether they have any of those.

Most likely they would reply "Some guy bought them all this morning."

"Sumgai" is the short form of "some guy," if you become a sumgai, then you're the lucky person who got to those yardsales (or antique fairs, online auctions, whatever) and bought those pricey pens or pen parts for a v low price before someone else came along and bought it.
You're looking for pens? I had a small box of plastic pens with veiny patterns on them, some in Black and White and some in Blood Red and Ivory. But sumgai came along this morning, mumbled something about a man called Patricia and offered me a $10 for them all. I asked for a $50, then he haggled down to $25. $25 for 4 plastic sticks ain't bad right?
by Gunther Wagner August 27, 2005
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